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(Italian, “glass with a small network”) A type of blown glass made with canes organized in a crisscross pattern to form a fine net, which may contain tiny air traps. vetro a reticelo Reticellos Reticelo Retichello Reticello Goblet

(Italian, “glass with twists”) A type of blown glass made with canes that have been twisted to form spiral patterns. vetro a retortis retortolis retortole retortoles retortis retortie retorte Retortoli Retorti Tazza

A beaker decorated with claw- or trunklike protrusions made by applying blobs of hot glass that melted the parts of the wall to which they were attached. The blobs were then blown outward and manipulated to resemble hollow claws. Claw beakers were made in Europe between the fifth and seventh

The process of reheating a blank until it becomes soft and gradually flows under its own weight over or into a former mold and eventually assumes the shape of the mold. Soda-lime glass becomes soft at about 1110°F (600°C). Slumping is also known as sagging. slump slumped slumps sagged Sagging Dish

(or: crisseling)The result of chemical instability in glass caused by an imbalance in the ingredients of the batch, particularly an excess of alkali or a deficiency of stabilizer (usually lime). The instability of the glass results in an attack by atmospheric moisture, which produces a network of